1969 K20 Towing Capacity - The 1947 - Present Chevrolet & GMC Truck Message Board Network

18436572GMC · 10-17-2013, 02:32 AM

How much could you safely and legally pull with a K20. SM465 NP205 383 stroker and front disc brakes.

jrdv · 10-17-2013, 04:57 AM

I've got the same setup on my 72. I figure I was hauling about 8000 lbs and had no problems. A panic stop might get you in trouble!

Main thing is to get your load balanced properly and give yourself plenty of stopping room.

marvgarr68 · 10-17-2013, 01:24 PM

I pull 12,000 pounds of water with my 76 k20. It has a built 350 I did my self a torque monster and a th350. The main thing is setting it up right make sure you have a trailer brake controller and trailer brakes. Put the load on the truck if it's not level reload or bye over loads air bags are great. With your combo you dont have to worry about overheating your trans. I had a 71 c20 with that trans and I moved a 50' mobile home 20 miles with it including through a wash never had a problem. Just be safe.

Keith Seymore · 10-17-2013, 08:16 PM

Quote:

Originally Posted by 18436572GMC

SM465 NP205 383 stroker and front disc brakes.

It also varies with rear axle ratio, due to launchability requirements. You have to be able to get rolling from a dead stop on a 16% grade at GCW (Gross Combined Weight - weight of the truck plus weight of the fully laden trailer).

According to this chart from the GM Heritage Center Archives info packet (page 101):

http://www.gmheritagecenter.com/docs...olet-Truck.pdf

you would be in the 10,000 to 11,000 lb GCW range using the 350 V8 or 396 V8 engines as a benchmark.

K

Prematuregrey · 10-17-2013, 09:24 PM

Really depends on gear ratio vs tire size. As far as pulling and handling the load, I feel the sky is the limit really, just make sure you are using trailer brakes and have the trailer loaded properly. My truck seems a little weak with 402/TH400 and 3.73's and 33-35" tires on long steepish hills towing around 8000#'s to me but I attribute that to the oversized tires it does tow very well on all other aspects. I'm looking at going up to 4.11's in the near future since I like the tire size I'm running. They have my speedo off around 5-7 mph slow around 60 (if speedo reads 60, I'm doing 65-67) which takes away from the engines power in the end.

18436572GMC · 10-17-2013, 09:36 PM

4.11 gears

Prematuregrey · 10-17-2013, 09:47 PM

You should have no problem dragging anything you want up to the hitch rating and beyond. Trailer brakes and AT cooler would be highly recommended though.

18436572GMC · 10-17-2013, 09:49 PM

Thanks for your input as it confirmed what I was thinking. Im not worried about the at cooler as it has a sm465

**special-K** · 10-18-2013, 10:01 AM

It can do it

62k10&84k20burb · 01-12-2014, 06:34 PM

Pull whatever you want! All the power in the world there. Ive pulled 8000lbs with a 2wd 1/2 ton ram

10-17-2013, 02:32 AM	#1
18436572GMC Registered User Join Date: Sep 2013 Location: iredell county, nc Posts: 77	1969 K20 Towing Capacity How much could you safely and legally pull with a K20. SM465 NP205 383 stroker and front disc brakes. __________________ Real trucks have a clutch. Please inform automakers. 1972 GMC, K25, 383 stroker, SM465, NP205, Eaton HO-72

10-17-2013, 04:57 AM	#2
jrdv Registered User Join Date: Apr 2000 Location: new mexico Posts: 948	Re: 1969 K20 Towing Capacity I've got the same setup on my 72. I figure I was hauling about 8000 lbs and had no problems. A panic stop might get you in trouble! Main thing is to get your load balanced properly and give yourself plenty of stopping room. Attached Images __________________ 1972 3/4T 4x4 Chevrolet (383) 1971 c-10 SWB (400 sb) 1972 4x4 Blazer 1969 SWB 4x4 GMC Projects: 1972 stepside 4x4 http://67-72chevytrucks.com/vboard/s...d.php?t=280132 http://67-72chevytrucks.com/vboard/s...d.php?t=285952 http://67-72chevytrucks.com/vboard/s...d.php?t=553672 http://67-72chevytrucks.com/vboard/s...d.php?t=522704

10-17-2013, 01:24 PM	#3
marvgarr68 Registered User Join Date: Jun 2013 Location: kingman az Posts: 573	Re: 1969 K20 Towing Capacity I pull 12,000 pounds of water with my 76 k20. It has a built 350 I did my self a torque monster and a th350. The main thing is setting it up right make sure you have a trailer brake controller and trailer brakes. Put the load on the truck if it's not level reload or bye over loads air bags are great. With your combo you dont have to worry about overheating your trans. I had a 71 c20 with that trans and I moved a 50' mobile home 20 miles with it including through a wash never had a problem. Just be safe. __________________ 1976 k20, 350 built, 44/14 axles 1968 c10 6.5 turbo diesel,t5 trans 1977 gmc c3500 dually, crew, 4-53t, 5&3 trans http://67-72chevytrucks.com/vboard/s...d.php?t=591188

10-17-2013, 09:24 PM	#5
Prematuregrey Registered User Join Date: Apr 2013 Location: Austin Texas Posts: 111	Re: 1969 K20 Towing Capacity Really depends on gear ratio vs tire size. As far as pulling and handling the load, I feel the sky is the limit really, just make sure you are using trailer brakes and have the trailer loaded properly. My truck seems a little weak with 402/TH400 and 3.73's and 33-35" tires on long steepish hills towing around 8000#'s to me but I attribute that to the oversized tires it does tow very well on all other aspects. I'm looking at going up to 4.11's in the near future since I like the tire size I'm running. They have my speedo off around 5-7 mph slow around 60 (if speedo reads 60, I'm doing 65-67) which takes away from the engines power in the end. __________________ Owner: Times Are Tough Toys 92 4 Runner (Joyce, long story from my time in Africa) Lotsa stuff, just about finished dumping money into it. 89 Mercedes 560 SEL, Merdle. Wrecked 71 Chevy K20, Clifford, BB and 1 Tons

10-17-2013, 09:36 PM	#6
18436572GMC Registered User Join Date: Sep 2013 Location: iredell county, nc Posts: 77	Re: 1969 K20 Towing Capacity 4.11 gears __________________ Real trucks have a clutch. Please inform automakers. 1972 GMC, K25, 383 stroker, SM465, NP205, Eaton HO-72

10-17-2013, 09:47 PM	#7
Prematuregrey Registered User Join Date: Apr 2013 Location: Austin Texas Posts: 111	Re: 1969 K20 Towing Capacity You should have no problem dragging anything you want up to the hitch rating and beyond. Trailer brakes and AT cooler would be highly recommended though. __________________ Owner: Times Are Tough Toys 92 4 Runner (Joyce, long story from my time in Africa) Lotsa stuff, just about finished dumping money into it. 89 Mercedes 560 SEL, Merdle. Wrecked 71 Chevy K20, Clifford, BB and 1 Tons

10-17-2013, 09:49 PM	#8
18436572GMC Registered User Join Date: Sep 2013 Location: iredell county, nc Posts: 77	Re: 1969 K20 Towing Capacity Thanks for your input as it confirmed what I was thinking. Im not worried about the at cooler as it has a sm465 __________________ Real trucks have a clutch. Please inform automakers. 1972 GMC, K25, 383 stroker, SM465, NP205, Eaton HO-72

10-18-2013, 10:01 AM	#9
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,851	Re: 1969 K20 Towing Capacity It can do it __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~

01-12-2014, 06:34 PM	#10
62k10&84k20burb Registered User Join Date: Apr 2013 Location: owls head, new york Posts: 81	Re: 1969 K20 Towing Capacity Pull whatever you want! All the power in the world there. Ive pulled 8000lbs with a 2wd 1/2 ton ram __________________ 62 k10 235/sm420 68 3500 250/sm465/eaton ho72/5.14s 84 burb k20 350/700r4/14bsf/10b 3.73s

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